Clinical profiles and modifiable risk factors for catheter-associated urinary tract infections in hospitalized obstetrics and gynecology patients: a case-control study.

A retrospective case-control study was conducted at the Obstetrics and Gynecology Hospital of Fudan University, a large tertiary university hospital in urban China. The hospital has 820 inpatient beds and provides healthcare services across 14 clinical and auxiliary departments, ensuring a sufficient patient population for this investigation. The study included all OB-Gyn inpatients with an indwelling urinary catheter during their hospitalization from November 1, 2021 to February 29, 2024. The inclusion criteria were as follows: (1) patients admitted for inpatient care in obstetrics or gynecology; and (2) the development of symptomatic CAUTI during hospitalization, defined as a urinary tract infection occurring either after catheter insertion or within 48 h of catheter removal, accompanied by clinical symptoms (e.g., fever, suprapubic tenderness, urinary tract irritation symptoms, or costovertebral angle pain) and a positive urine culture. The exclusion criteria included: (1) confirmed urinary tract infection present at the time of admission; (2) incomplete data on essential study variables or indicators within the electronic medical record system; and (3) current use of psychotropic medications. This study was approved by the Ethics Committee of the Obstetrics and Gynecology Hospital of Fudan University (Approval No.2024 − 181). All data collection and analysis were conducted after obtaining ethical approval. Given that this study was a retrospective analysis of medical records, the Ethics Committee waived the requirement for obtaining individual informed consent from participants. Our study adhered to the Declaration of Helsinki, and all methods were performed in accordance with the Ethical Review of Life Science and Medical Research Involving Human Subjects issued by the National Health Commission of China. Prior to data collection, a sample size calculation was performed using PASS software (version 2021). Based on an odds ratio (OR) of 2.571 and an expected proportion of exposure in the control group (p 0 ) of 0.5469, derived from prior literature [ 21 ], and accounting for an estimated 20% rate of incomplete data, the calculation determined that 122 patients were required for each group (case and control) to achieve sufficient statistical power. The case group was defined as all consecutive OB-Gyn inpatients ( n = 131) who developed a symptomatic CAUTI during their hospitalization between November 1, 2021 and February 29, 2024. A comprehensive review of hospital infection control records and laboratory data confirmed that no other eligible CAUTI cases meeting the study’s diagnostic criteria were identified during this period. The control group consisted of patients without CAUTI who were individually matched to each case at a 1:1 ratio. The matching criteria were rigorously defined and applied in the following order to ensure comparability: (1) Hospitalization period : Controls were selected from patients admitted to the same ward within the same calendar week as the corresponding case; (2) Primary diagnosis : Within that pool, priority was given to matching based on the primary admission diagnosis (e.g., benign ovarian cyst, uterine fibroids, cervical cancer) to control for underlying disease-related risks; (3) Treatment type : Whenever possible, we further matched controls to cases based on the type of treatment received (e.g., major laparoscopic surgery, transabdominal surgery, or medical management) to account for procedural risks; and (4) Age : We aimed to select a control patient of similar age (± 5 years). This multi-step matching process was designed to minimize confounding by these key clinical and demographic factors. Clinical data for all participants were extracted retrospectively from the hospital’s electronic medical record system. Two trained researchers independently extracted clinical data using standardized search protocols with predefined inclusion/exclusion filters. All extracted variables were systematically recorded in a pre-designed Excel template to ensure consistent formatting, followed by comprehensive manual validation against primary source documents. Collected variables included basic patient information (e.g., age, height, weight, education level), medical data (e.g., length of hospital stay, primary and secondary diagnoses (including chronic comorbidities), surgical history, relevant laboratory test results, antibiotic usage history, nutritional screening status on admission), and catheter-specific data (e.g., indication for catheterization, date and time of catheter insertion and removal, total duration of catheterization, number of catheterizations, environment where catherization was performed, occurrence of any adverse events during catheterization or dwelling time, and whether the patient was discharged with an indwelling catheter). Discrepancies such as undocumented catheter removal times were addressed by triangulating data from nursing flow sheets and physician orders. Any unresolved cases were subjected to a consensus review by a third investigator. Clinically improbable values were further examined through a secondary chart review and validated against medication administration records to confirm their accuracy. This dual-phase extraction and validation process ensured the robustness of data quality throughout the study period. The CAUTI incidence density was calculated as the number of CAUTI cases per 1,000 catheter-days. The total number of catheter-days for all OB-Gyn inpatients during the study period was obtained from the hospital’s infection control department. To ensure consistency and minimize procedural variation, all catheter-related practices in the study hospital were governed by standardized protocols aligned with the Technical Guideline for the Prevention and Control of Catheter-Associated Urinary Tract Infection (Ministry of Health of China, 2010). The key specifications implemented in this study were as follows: (1) Indication and authorization : Catheterization was performed only upon a physician’s order for accepted clinical indications, such as intraoperative monitoring, management of urinary retention, or accurate measurement of output in critically ill patients; (2) Performing personnel : The procedure was carried out by trained, licensed nursing staff who had completed competency-based training on aseptic catheter insertion and maintenance; (3) Insertion technique : A strict aseptic technique was mandatory, including performing hand hygiene, wearing sterile gloves, using a single-use catheterization kit, and thoroughly disinfecting the urethral meatus and perineal area with iodophor solution; (4) Catheter material and drainage system : Sterile, single-use, 16–18 Fr non-antibiotic antimicrobial catheter were used with a pre-connected, closed and sterile drainage system; and (5) Maintenance care : The closed system was preserved; the drainage bag was kept below the level of the bladder; daily perineal hygiene was performed, and the catheter was secured to the patient’s thigh to prevent urethral traction and movement. These standardized practices, reinforced through regular nursing education and audits, help mitigate the confounding effect of variable techniques, allowing the patient-level factors investigated in this study to be more clearly discerned. The diagnosis of CAUTI adhered strictly to the criteria outlined in the Technical Guideline for the Prevention and Control of Catheter-Associated Urinary Tract Infection issued by the Ministry of Health of China in 2010. The choice of Chinese standards was based on their widespread adoption in local clinical practice and historical consistency within our institutional data systems. A diagnosis required the presence of clinical manifestations alongside specific microbiological or direct evidence criteria. This study defines clinical diagnosis as the presence of urinary tract irritation in patients, characterized by symptoms such as frequent urination, urgency, pain during urination, lower abdominal tenderness, renal percussion pain, with or without fever, and a white blood cell count of ≥ 10/high power field for females. Urine cultures must be obtained from patients with urinary catheters. At least one of the following criteria must be met: (1) The count of Gram-positive cocci cultured from clean midstream urine or urine collected by non-indwelling catheterization is ≥ 10 4  cfu/ml, and the count of Gram-negative bacilli cultured is ≥ 10 5  cfu/ml; (2) The count of bacterial colonies cultured from urine collected by suprapubic bladder puncture is ≥ 10 3  cfu/ml; (3) Fresh urine specimens are centrifuged and examined using a phase contrast microscope, with bacteria observed in at least half of every 30 fields of view; and (4) Evidence of urinary tract infection is confirmed through surgical, pathological, or imaging examinations. Urine samples for pathogenetic testing were collected from patients suspected of having CAUTI and transported to the clinical microbiology laboratory within two hours of collection. Pathogen identification and antimicrobial susceptibility testing were conducted in accordance with the National Clinical Microbiology Laboratory Diagnostic Criteria for Urinary Tract Infections. To prevent duplicate reporting, only the first isolate of each bacterial or fungal species from a given patient was included in the analysis, irrespective of any subsequent positive cultures of the same organism. The collected data were numbered and entered into SPSS 20.0 (IBM, Inc., Armonk, NY) for statistical analysis. Consistent with our exclusion criteria, cases with incomplete essential variables were removed prior to analysis, resulting in a complete-case dataset. Categorical data were compared between groups using the Chi-square test. Continuous data with a normal distribution are presented as means (± s.d.), while medians (inter-quartile ranges [IQR]) are reported for non-normal distributions. Categorical variables are expressed as counts (percentages). The independent variables included in this study were selected a priori based on their clinical relevance and established associations with CAUTIs as reported in the literature [ 22 – 24 ]. These variables included: patient demographics (age, education level), clinical characteristics (type of treatment, body mass index (BMI), length of hospital stay, nutritional status, hemoglobin, total protein, and albumin levels), comorbidity profile (e.g., hypertension, diabetes, anemia, chronic nephritis), surgical history, and catheter-related factors (indication, duration, frequency, environmental conditions, and discharge status with catheter). Initially, all pre-selected variables were evaluated using univariate analysis to assess their unadjusted associations with CAUTIs. Given the case-control design, McNemar’s test was used to compare categorical variables between cases and controls, which assesses the symmetry of discordant pairs within each matched set. Continuous variables were compared using paired t-tests or Wilcoxon signed-rank tests, as appropriate. Variables that exhibited a univariate P value < 0.05, along with those considered clinically critical based on prior evidence, were included as candidates in the multivariate logistic regression model. A forward conditional approach was employed to identify independent risk factors, with results reported as odds ratios (ORs) and 95% confidence intervals (CIs). A two-sided P- value < 0.05 was regarded as statistically significant.

A total of 262 hospitalized patients in OB-Gyn were included in the study. Among these, 36 patients (13.7%) were obstetric patients, while 226 patients (86.3%) were gynecological patients. The median age of the patients was 44 years (IQR = 19.0), with a mean BMI of 23.2 kg/m 2 (IQR = 5.1). The median length of hospital stay was 9 days (IQR = 7.0), and 27 patients (10.3%) were identified as being nutritionally at-risk upon admission (Table  1 ). In the CAUTI group ( n  = 131), the clinical features were pre-dominantly characterized by fever ( n  = 112, 85.5%), urinary occult blood ( n  = 92, 70.2%), abnormalities in urinary blood cell tests ( n  = 82, 62.6%), abnormalities in urinary white blood cell tests ( n  = 73, 55.7%), and abnormalities in urine protein tests ( n  = 71, 54.2%). During the study period (November 2021 to February 2024), a total of 56,854 patients with indwelling urinary catheters were admitted to the obstetrics and gynecology departments, accounting for 102,540 total catheter-days. Among them, 131 patients developed a symptomatic CAUTI. The CAUTI incidence density was therefore calculated to be 1.28 per 1,000 catheter-days. Table 1 Baseline characteristics of the patients Characteristics Patients (%) ( n  = 262) Age (years) , median (IQR) 44 (33–52) Department [n (%)]  Gynecology 226 (86.3)  Obstetrics 36 (13.7) Type of diagnosis [n (%)]  Tumour 188 (71.8)  Caesarean section 14 (5.3)  Endometriosis and adenomyosis 14 (5.3)  Vaginal delivery 13 (5.0)  Predelivery 10 (3.8)  Others 23 (8.8) BMI (kg/m 2 ) , median (IQR) 23.2 (20.9–26.0) Hospital stay (days) , median (IQR) 9 (6–13) Level of education [n (%)]  High school degree or below 138 (52.7)  Junior college or university degree 103 (39.3)  Master’s degree or above 21 (8.0) Type of treatment [n (%)]  Laparoscopic surgery 141 (53.8)  Medical therapy 47 (17.9)  Transabdominal surgery 40 (15.3)  Transvaginal surgery 29 (11.1)  Cystoscopic surgery 5 (1.9) Being nutritionally at-risk upon admission [n (%)] 27 (10.3) Clinical manifestations [n (%)](n = 131)  Fever, n (%) 112 (85.5)  Urinary tract irritation symptoms, n (%) 17 (13.0)  Maximum body temperature (°C), mean ± s.d.  38.3 ± 0.7 Urinalysis findings [n (%)] (n = 131)  Occult blood 92 (70.2)  Abnormalities in urinary red blood cell tests 82 (62.6)  Abnormalities in urinary white blood cell tests 73 (55.7)  Abnormal urine protein 71 (54.2)  Positive urine nitrite 27 (20.6) Catheter Data [n (%)] (n = 131)  Duration of catheterization (days), median (IQR) 5 (2–10)  Catheter retention at discharge, n (%) 40 (30.5) Baseline characteristics of the patients A total of 133 strains of pathogens were identified in the urine of 131 hospitalized patients with CAUTIs. The majority of these pathogens were gram-negative bacteria ( n  = 107, 80.5%), followed by gram-positive bacteria ( n  = 17, 12.8%) and fungi ( n  = 9, 6.8%). In addition, each of three patients had two different pathogens detected ( Escherichia coli and Candida albicans ), while no pathogens were identified in the 48-hour urine culture of one patient. Among the gram-negative bacteria, Escherichia coli was the most prevalent ( n  = 79, 59.4%), followed by Klebsiella pneumoniae ( n  = 7, 5.3%) and Pseudomonas aeruginosa ( n  = 5, 3.8%). Enterococcus faecalis ( n  = 14, 10.5%) was the most common gram-positive bacterium, and Candida albicans ( n  = 8, 6.0%) was the most frequently detected fungus. For temporal distribution analysis, the data were grouped as follows: the complete calendar years of 2022 and 2023 were divided into standard quarters (Q1: January-March; Q2: April-June; Q3: July-September; Q4: October-December). The data from the partial years at the start and end of the study period were assigned to the nearest logical quarter: November–December 2021 was included in Q4, and January–February 2024 was included in Q1. Within this framework, the highest absolute number of isolates was observed in the initial phase of the study (Q1: n  = 42, 31.6%) (Table  2 ). To account for variations in patient volumes and catheter utilization over time, we calculated the CAUTI incidence density (cases per 1,000 catheter-days) for each quarter. The total catheter-days recorded were 27,616 for Q1, 17,554 for Q2, 25,107 for Q3, and 32,263 for Q4. The number of CAUTI cases documented in these quarters was 43, 32, 23, and 33, respectively. Consequently, the CAUTI incidence rates were 1.56, 1.82, 0.92, and 1.02 per 1,000 catheter-days. Table 2 Time distribution of pathogenic bacteria in urine culture of patients with CAUTIs Pathogen Q1 Q2 Q3 Q4 Total Gram-negative bacteria[n (%)] 36 (27.1) 25 (18.8) 19 (14.3) 27 (20.3) 107 (80.5)  Escherichia coli 30 (22.6) 16 (12.0) 14 (10.5) 19 (14.3) 79(59.4)  Klebsiella pneumoniae 0 (0.0) 4 (3.0) 3 (2.3) 0 (0.0) 7(5.3)  Pseudomonas aeruginosa 0 (0.0) 0 (0.0) 2 (1.5) 3 (2.3) 5 (3.8)  Other gram-negative bacteria a 6(4.5) 5(3.8) 0(0.0) 5(3.8) 16(12.0) Gram-positive bacteria[n (%)] 6 (4.5) 5 (3.8) 2 (1.5) 4 (3.0) 17 (12.8)   Enterococcus faecalis 5 (3.8) 3 (2.3) 2 (1.5) 4 (3.0) 14 (10.5)  Other gram-positive bacteria b 1(0.8) 2(1.5) 0(0.0) 0(0.0) 3(2.3) Fungi[n (%)] 0 (0.0) 2 (1.5) 3 (2.3) 4 (3.0) 9 (6.8)  Candida albicans 0 (0.0) 2 (1.5) 2 (1.5) 4 (3.0) 8 (6.0)  Candida tropicalis 0 (0.0) 0 (0.0) 1 (0.8) 0 (0.0) 1 (0.8) Total[n (%)] 42 (31.6) 32 (24.1) 24 (18.1) 35 (26.3) 133(100.0) a Other gram-negative bacteria include Enterobacter xiangfangensis, Enterobacter aerogenes, Morganella morganii, Enterobacter cloacae, Proteus mirabilis, Enterobacter asburiae, Proteus vulgaris, Proteus penneri and Citrobacter koseri . b Other gram-positive bacteria include Actinomyces, Enterococcus gallinarum and Staphylococcus epidermidis Time distribution of pathogenic bacteria in urine culture of patients with CAUTIs a Other gram-negative bacteria include Enterobacter xiangfangensis, Enterobacter aerogenes, Morganella morganii, Enterobacter cloacae, Proteus mirabilis, Enterobacter asburiae, Proteus vulgaris, Proteus penneri and Citrobacter koseri . b Other gram-positive bacteria include Actinomyces, Enterococcus gallinarum and Staphylococcus epidermidis A total of 265 instances of antibiotic courses were prescribed among 131 patients with CAUTIs. Among these prescriptions, cefuroxime sodium ( n  = 67, 25.3%), amikacin ( n  = 33, 12.5%), and levofloxacin ( n  = 32, 12.1%) were the most commonly used antibiotics for CAUTI management (Fig.  1 ). Fig. 1 History of antibiotic use in patients with CAUTIs during hospitalization History of antibiotic use in patients with CAUTIs during hospitalization A total of seven risk factors were identified as significantly correlated with CAUTIs ( P  < 0.05). These factors include the presence of chronic diseases, being nutritionally at-risk upon admission, the duration of catheterization, multiple catheterizations (≥ 2), the environment in which catheterization occurs, discharge with an indwelling urinary catheter, and a prolonged hospital stay exceeding 7 days (Table  3 ). Table 3 Univariate analysis of risk factors in patients with CAUTIs Characteristics CAUTI group ( n  = 131) Non-CAUTI group ( n  = 131) Statistic P value Combined with chronic diseases [n (%)] 9.570 a 0.002  Yes 49 (37.4) 46 (35.1)  No 82 (62.6) 85 (64.9) Being nutritionally at-risk upon admission [n (%)] 93.061 a < 0.001  Yes 22 (16.8) 5 (3.8)  No 109 (83.2) 126 (96.2) Duration of catheterization (days), median 5 (2–10) 3 (2–4) 14.873 b < 0.001 Usage of urinary catheterization [n (%)] 106.080 a < 0.001  Once 111 (84.7) 130 (99.2)  Twice or more 20 (15.3) 1 (0.8) Environment of catheterization [n (%)] 75.409 a < 0.001  Operating theatre 110 (84.0) 128 (97.7)  Not operating theatre 21 (16.0) 3 (2.3) Discharge with an indwelling urinary catheter [n (%)] 67.919 a < 0.001  Yes 40 (30.5) 8 (6.1)  No 91 (69.5) 123 (93.9) Hospital stay (days) [n (%)] 20.452 c  14 36 (27.5) 14 (10.7) a McNemar Chi-square test; b t test; c Chi-square test Univariate analysis of risk factors in patients with CAUTIs a McNemar Chi-square test; b t test; c Chi-square test To elucidate the independent risk factors for CAUTIs in obstetrics and gynecology, a multivariate logistic regression analysis was performed using 13 variables included in the study: type of treatment, level of education, age, length of hospital stay, BMI, presence of chronic diseases, history of surgeries, results of nutrition screening tests, frequency of catheterization, catheterization environment, discharge status with urinary catheter, haemoglobin level, and duration of catheterization. The variable assignments are presented in Appendix 1. We identified four independent risk factors for CAUTIs in OB-Gyn, detailed as follows: being nutritionally at-risk upon admission (OR = 4.189, 95% CI: 1.402 ~ 12.513, P  = 0.010), discharge with an indwelling urinary catheter (OR = 5.526, 95% CI: 2.352 ~ 12.985, P  < 0.001), multiple catheterizations (≥ 2) (OR = 16.642, 95% CI: 2.057 ~ 134.617, P  = 0.008), and a hospital stay exceeding 7 days (OR = 2.547, 95% CI: 1.423 ~ 4.560, P  = 0.002) (Table  4 ). Table 4 Multivariate regression analysis of risk factors associated with CAUTIs Risk factors B SE Wald P OR 95%CI Constant 0.000 0.124 0.000 1.000 1.000 — Being nutritionally at-risk upon admission 1.432 0.558 6.582 0.010 4.189 1.402–12.513 Discharge with an indwelling urinary catheter 1.710 0.436 15.385 < 0.001 5.526 2.352–12.985 Multiple catheterizations (≥ 2) 2.812 1.067 6.950 0.008 16.642 2.057-134.617 Hospital stay exceeding 7 days 0.935 0.297 9.901 0.002 2.547 1.423–4.560 Multivariate regression analysis of risk factors associated with CAUTIs

CAUTIs pose a significant clinical threat in OB-Gyn inpatient settings, primarily characterized by fever and occult hematuria, with infections caused by Escherichia coli being the most common etiological pattern. This study identifies four modifiable risk factors for targeted interventions, including being nutritionally at-risk upon admission, discharge with indwelling catheters, multiple catheterizations (≥ 2), and hospitalization exceeding 7 days. To mitigate these risks, evidence-based prevention strategies should prioritize nutritional vigilance through screening for recent weight loss or reduced dietary intake, implement rigorous catheter minimization protocols to avoid unnecessary insertions, ensure strict adherence to aseptic techniques during insertion and maintenance, and establish structured transition planning for discharged patients with catheters. This planning should encompass comprehensive education on home care, infection recognition, and telehealth-supported follow-up. Nurses play a pivotal role in integrating these multifaceted approaches to reduce the incidence of CAUTIs and enhance patient safety within OB-Gyn care environments.

This study compared the clinical characteristics between CAUTI and non-CAUTI groups among OB-Gyn inpatients with indwelling urinary catheters. Fever and urinary occult blood were the predominant clinical findings, while lower urinary tract symptoms, such as urgency and dysuria, were less frequent. This observation aligns with established clinical patterns, where systemic symptoms like fever suggest upper urinary tract involvement, whereas irritative symptoms typically indicate lower urinary tract infections [ 21 ]. Notably, patients with CAUTIs experienced significantly prolonged hospital stays, consistent with literature indicating an additional 1–2 days of hospitalization attributable to CAUTIs [ 25 ]. This highlights the necessity for clinical nurses to promptly differentiate CAUTIs from other febrile causes and initiate targeted interventions to improve patient outcomes. Escherichia coli was identified as the predominant pathogen responsible for CAUTIs in OB-Gyn patients, corroborating global trends in the etiology of CAUTIs [ 26 – 30 ]. As a commensal gut bacterium and environmental contaminant, Escherichia coli is a common inhabitant of the human gut and the environment, especially in freshwater. When the immune function of the body is compromised, or when patients undergo invasive procedures in the urinary system, or when individuals are exposed to contaminated environments, this bacterium can lead to urinary tract infections [ 31 ]. This reinforces the importance of pathogen-directed antibiotic selection to optimize therapeutic efficacy and mitigate resistance [ 7 ]. In our study, one case showed no microbial growth in 48-hour urine cultures, potentially due to pre-analytical errors in specimen handling. This finding highlights the necessity for strict adherence to aseptic collection and prompt transport protocols [ 32 ]. Furthermore, cases of polymicrobial infection warrant careful clinical management due to its implications for treatment complexity [ 15 ]. The profile of antibiotic use in our CAUTI patients provides important insights into empirical treatment strategies at our institution. The most frequently prescribed agents, namely cefuroxime (25.3%), amikacin (12.5%), and levofloxacin (12.1%), are consistent with guidelines for managing hospital-acquired UTIs and reflect a targeted approach toward the predominant gram-negative pathogens found in our study, particularly Escherichia coli [ 26 – 30 ]. The use of amikacin and levofloxacin, in particular, may indicate their role as alternatives or second-line agents for infections suspected or proven to be caused by resistant organisms. This pattern generally aligns with reported practices in other settings [ 33 , 34 ]. However, the considerable use of these agents also underscores the importance of ongoing antimicrobial stewardship. Prompt transition from empirical to pathogen-directed therapy, based on antimicrobial susceptibility testing results, is crucial to optimize efficacy and curb the emergence of resistance. Our study compared the relative proportions of the predominant pathogens in CAUTIs and calculated the quarterly incidence density of infection across different time periods. The growth rate of Escherichia coli , the predominant pathogen responsible for CAUTIs, is influenced by variations in temperature and humidity [ 35 , 36 ]. Our findings showed that both Q1 and Q2 exhibited incidence rates above the overall study average, with the highest rate observed in Q2. This pattern may reflect the effects of rising temperatures and increased humidity during these periods, which could promote bacterial proliferation and transmission. Consequently, reinforcing seasonal infection control measures [ 37 , 38 ], such as strengthening environmental hygiene, ensuring adequate ward ventilation, and encouraging adequate fluid intake, may help mitigate the elevated risk. However, as the observation periods at the beginning and end of the study were not of equal length, future research on seasonal variation should adopt complete and standardized calendar intervals and statistical models adjusted for pertinent clinical and environmental confounders. In this study, multivariable analysis identified four key modifiable risk factors for CAUTIs in OB-Gyn inpatients. Firstly, patients who were screened as being nutritionally at-risk upon admission faced a significantly elevated risk of CAUTIs. This heightened risk is likely attributable to compromised host immune defenses associated with malnutrition [ 39 ], necessitating dynamic nutritional risk assessments and targeted interventions aimed at mitigating CAUTI risks. Existing evidence suggests that nutritional optimization should be incorporated as a key preventive strategy against CAUTIs in surgical patients. Addressing nutrition-related complications may confer protective benefits against urological disorders [ 40 ]. Furthermore, probiotic supplementation, whether through dietary sources or dedicated preparations, has been shown to be effective in reducing recurrent urinary tract infections [ 41 ]. Secondly, a hospital stay exceeding 7 days was identified as an independent risk factor for CAUTIs. This finding necessitates a context-specific interpretation. While indwelling catheterization beyond 10 days is a critical risk factor in general populations [ 5 ], our obstetrics and gynecology cohort is characterized by substantially shorter median catheterization durations. Therefore, the conventional 10-day catheterization benchmark is less applicable for defining high-risk exposure in our setting. Instead, we selected a 7-day cutoff for total hospitalization based on the clinical profile of our specialty, where this duration often signifies a transition from a routine postoperative recovery to a more complicated clinical course. A prolonged stay inherently expands the window of exposure to nosocomial pathogens and increases the likelihood of undergoing additional invasive procedures [ 42 ]. This risk may be further compounded by the potential immunosuppressive effects of anxiety and stress associated with lengthy admissions [ 43 ]. Consequently, for OB-Gyn inpatients, a hospital stay exceeding 7 days should serve as a key indicator triggering intensified nursing surveillance and preventive care [ 44 ]. Thirdly, discharge with an indwelling urinary catheter was a significant risk factor for CAUTIs. This practice inherently prolongs the duration of catheterization, as patients typically require continued catheter use for a period ranging one week to one month post-discharge, depending on their clinical needs, often exceeding the 10-day threshold. Indwelling catheterization beyond 10 days is a well-established independent risk factor for CAUTIs [ 5 ]. The transition to home care presents specific challenges; inadequate knowledge of sterile techniques among patients and caregivers heightens the risk of improper catheter maintenance and subsequent infections [ 45 ]. To address this issue, we advocate for the implementation of a comprehensive discharge protocol. This protocol should include structured patient education on aseptic catheter care, the development of personalized catheter removal plans, and the establishment of robust follow-up systems utilizing telehealth platforms to ensure continuity of care and prevent community-onset CAUTIs [ 46 – 48 ]. Fourthly, patients undergoing multiple catheterizations (≥ 2) had a significantly increased risk of developing CAUTIs. Repeated insertions cause mechanical trauma to the urethral mucosa, disrupting natural protective barriers and facilitating the ascent of perineal bacteria, leading to retrograde urinary tract infections [ 15 ]. Therefore, minimizing unnecessary re-catheterization is crucial. Alternatives such as hot compresses and perineal flushing with warm water should be considered to manage issues like urinary retention and to reduce catheter dependence [ 49 , 50 ]. While the median duration of catheterization was significantly longer in the CAUTI group than in the control group in the univariate analysis, this variable did not emerge as an independent risk factor in the multivariate model. This may be attributed to the effect of prolonged catheterization being largely mediated through other factors identified in this study, such as discharge with a catheter, multiple catheterizations, and hospital stay exceeding 7 days. These variables are closely associated with extended catheter use and may account for the risk previously attributed to duration alone. Evidence from previous studies indicates that shorter catheterization durations are associated with a reduced risk of symptomatic CAUTI compared to longer durations [ 51 ]. Therefore, reducing unnecessary catheter days and promoting timely catheter removal remain essential components of CAUTI prevention strategies. This study has several limitations that should be considered when interpreting the findings. First, its single-center design and retrospective nature may affect the generalizability of the results. Second, although we reported the CAUTI incidence density based on data from the hospital infection control department, the diagnostic criteria employed adhered to Chinese national standards (Ministry of Health, 2010), which may differ in certain aspects from those of the Centers for Disease Control and Prevention/National Healthcare Safety Network (CDC/NHSN). To mitigate potential misclassification, we strictly included only symptomatic CAUTI cases, aligning with the CDC/NHSN principle of excluding asymptomatic bacteriuria. Furthermore, the study cohort primarily consisted of women of reproductive age, with limited representation of elderly patients, who constitute a known high-risk group for CAUTIs [ 4 ]. Although our hospital serves a diverse urban population, enhancing the relevance of our findings to similar tertiary care settings, the findings should be validated in broader populations. Future research should employ multicenter, prospective cohort designs with larger and more demographically diverse samples, including adequate representation of elderly patients. Incorporating additional clinically relevant variables will further help to comprehensively evaluate CAUTI risks and strengthen the evidence base for prevention in OB-Gyn populations.

Catheter-associated urinary tract infections (CAUTIs) are defined as urinary tract infections occurring during urinary catheterization or within 48 h after catheter removal [ 1 ]. As one of the most prevalent healthcare-associated infections [ 1 ], CAUTIs account for approximately 20% of hospital-acquired bacteremia [ 2 ]. Epidemiological data indicate a significant global burden, with studies in China reporting that 20% to 60% of patients undergoing urinary catheterization develop urinary tract infections, 80% of which are directly attributable to indwelling catheters [ 3 ]. Similarly, the US surveillance data reveal that 25% of hospitalized patients develop CAUTIs [ 4 ]. Among elderly inpatients, CAUTIs represent the second most common nosocomial infection after pneumonia, largely due to comorbidities and age-related immune decline [ 5 ]. Women are recognized as a high-risk group for CAUTIs due to a combination of physiological and anatomical factors [ 6 ]. The perineal region in females exhibits a higher colonization rate of pathogenic microorganisms, which increases the likelihood of infection. Anatomically, the female urethra is shorter and straighter than that of male's, and the urethral sphincter is relatively weaker. These characteristics facilitate the ascent of microorganisms into the bladder [ 7 ]. Furthermore, the proximity of the female urethral orifice to the anus increases the risk of contamination by intestinal flora, particularly Escherichia coli , a leading cause of urinary tract infections [ 8 ]. Obstetrics and gynecology (OB-Gyn) procedures, especially transvaginal and transabdominal surgeries, pose an additional risk by potentially damaging or contaminating the urethra and bladder, thus creating favorable conditions for bacterial entry and colonization [ 9 , 10 ]. Pregnancy further elevates the risk due to urethral relaxation and reduced urinary flow, both of which impair the natural flushing mechanism of the urinary tract [ 11 ]. Other risk factors include advanced age (greater than 70 years), characterized by immunosenescence and the presence of chronic comorbidities [ 12 ]; postmenopausal estrogen deficiency leading to degeneration of the urethral mucosa [ 13 ]; and prolonged catheterization, which disrupts natural defenses and promotes biofilm formation on catheter surfaces [ 14 ]. In addition, improper catheter insertion techniques, violations of aseptic protocols, and insufficient perineal hygiene can directly introduce pathogens or facilitate their migration into the urinary tract [ 15 ]. Comorbid conditions such as anemia [ 16 ] and diabetes [ 17 ] also heighten the risk of infection, with diabetes creating a glucose-rich environment that facilitates bacterial growth. The material of the catheter itself can affect infection risk; for instance, plastic catheters exhibit a higher propensity for bacterial adhesion compared to alternative materials [ 18 ]. Other contributing factors include patient immobility, inadequate daily fluid intake, and the presence of severe underlying health conditions [ 19 ]. CAUTIs generate substantial clinical and economic burdens, exacerbating patient’s underlying conditions, prolonging hospitalization, and increasing healthcare costs [ 20 ]. Although optimized urinary catheter management protocols can effectively reduce the incidence of CAUTIs [ 1 ], significant knowledge gaps persist, particularly concerning OB-Gyn populations. Healthcare providers often exhibit insufficient awareness of female-specific CAUTI risks [ 12 ], and the current literature lacks a comprehensive analysis of the clinical profiles and modifiable risk factors of CAUTIs specific to OB-Gyn inpatients. Consequently, existing prevention strategies may inadequately address the unique vulnerabilities of this population. Therefore, this case-control study aimed to identify the clinical profiles and modifiable risk factors for CAUTIs among hospitalized OB-Gyn patients in a large tertiary hospital in China. The findings are intended to inform the development of evidence-based, population-specific prevention strategies.

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